STAR-CCM+ v7 Workflow Process

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2 v7refguide02_2012 STAR-CCM+ v7 Workflow Process From Geometry Creation & Import Import a surface/cad geometry File > Import Surface or Click Import, Edit or Create a New Geometry using 3D-CAD Right click on 3D models > New + Right Click on a Plane > Create Sketch + Right Click on a Sketch > Choose 3D Feature Operation Turn 3D-CAD Model into a Region Rename Faces in 3D-CAD for Boundaries + Close 3D-CAD > Right Click on Model > New Geometry Part + Right Click on Part > Choose Region > New Available 3D Operations: Sweep, Loft, Extrude, Revolve, Fillet, Chamfer, Pattern, Booleans, Flow Domain Extraction Design parameters: Allows parameters to be modified without having to edit the 3D model STAR-CCM+ v7 Quick Reference Guide 02

3 ...To Mesh Generation Creating a Mesh Continuum Right click on Continue > New + Select Mesh + Right click Mesh > Select Models Meshing Models Surface Wrapper (Not always required) Fluid volume extraction Complex assembly simplification Provide closed surface on poor quality CAD Surface Remesher (Required) To improve quality of surface triangulation Trimmer More efficient at filling large volumes Uses less memory per cell Polyhedral Mesher Well suited to complex, multi-region geometries Converges quickly Prism Layer Mesher Used to generate prisms next to walls Extruder Used to offset boundaries Useful for cell count/meshing time reduction Thin Mesher Create prisms in thin objects Reduces cell count for thin objects Advancing Layer Mesher Used to create thicker layers of polyhedral prisms Effective for external aerodynamics, hydrodynamics etc Setting up the Physics... Creating a Physics Continuum Right click on Continua > New + Select Physics + Right click on new continua > Select Models + Essential models use round check box, optional use square Tip: Auto-select option will choose most commonly used models Creating Reports and Monitors Right click Reports > New + Select desired type of report + Define included parts and units to return + Right click on the new report > create monitor and plot from report To create field monitors + Right click Monitors + New Monitor Tip: Multiple reports can be put in one plot Generalized Cylinder Meshes cylindrical shapes with prismatic cells Effective meshing of pipelines, manifolds, etc. Meshing Rules of thumb Minimum of 4-5 cells across a thin channel For flows where heat transfer or lift/drag is important - At least 15 cells in the prism layer - Y+ values should be less than 3 Refine where there are high gradients - Recirculation - Jet flows - High temperature gradients Tip: Always look at the engineering quantities that need to be derived from the simulation! Volumetric Controls Right click on Volumetric Controls > New + Choose shape or any part for control + Provide custom size for polyhedral & surface meshers + Isotropic and anisotropic refinement of trim meshes + Custom settings for prism layers Local Mesh Settings Region specific settings - Refine a porous media or thin wall solid Boundary specific settings - Small geometry relative to over all size - Special boundary layer needs - Bounding box may need coarser settings Monitoring Convergence Residuals - Should decrease by 2-3 orders of magnitude Engineering Values - Area or Mass averaged - Volume Averaged - Maximums or Minimums - Flow Rates - Forces/Moments or coefficients Flowfield - Create Scalar or Vector scenes to provide visual confirmation of simulation setup In case of divergence, check: Boundary conditions - location, values, validity Initial conditions Correct physics models applied Mesh quality and density Solver controls - under relaxation, courant number STAR-CCM+ v7 Quick Reference Guide 03

4 Setting up the Physics...continued Overset Meshes To model extreme ranges of motion between multiple bodies, easily swap parts, change body positions To use overset meshes: - Outer boundaries of overset region should be "overset mesh" type - Select the background and overset region right click > Create Interface > Overset Mesh Modeling Motion In tools right click on motions > New + User Specified motion - Rotation - Rotation & Translation - Morphing - Harmonic Balance Flutter + Dynamic Fluid Body Interaction (DFBI) - Rotation & Translation - Embedded Rotation - Morphing - Superposed rotation + Solid Displacement Modeling Space - 2D, Axisymmetric, 3D, Shell 3D Time - Steady-state, Unsteady Implicit, Unsteady Explicit, Harmonic Balance Material - Gas, Liquid or Solid single components - Gas, Liquid or Solid multi-components - Immiscible phases, VOF & Eulerian Multiphase Flow - Coupled Flow and Coupled Energy: for compressible flows, shock waves, natural convection, large body sources, energy sources: for subsonic up to hypersonic flows - Segregated Flow and Segregated Fluid Energy: for most sub sonic flows, Lagrangian multiphase for droplet modeling Viscous regime - Inviscid: for high-reynolds compressible aerodynamics - Laminar - Turbulent (3 approaches: RANS, LES, DES) K-Epsilon: generally well suited to industrial-type applications K-Omega: good for low speed external aero (Automotive or Aerospace), captures wake better than K-E model Gamma ReTheta: Transition model from laminar to turbulent regimes Spalart-Allmaras: Predominantly used in Aerospace, good for attached flow around streamlined bodies Reynolds Stress Transport: Works best for cyclone separators where flow is highly anisotropic Multiphase models: - Volume of Fluid VOF - To model immiscible mixtures with a sharp free surface between phases - Supplementary models: Boiling, cavitation, surface evaporation & condensation, melting-solidification, wave generation - Eulerian Multiphase - To model mixtures of discrete phases, such as powders, bubbly flows etc - Supplementary models: Interphase drag laws for different flow types, solid pressure force, S-Gamma population balance, boiling, gas dilution, permeable boundaries - Lagrangian Multi-phase - To study the behavior of droplets and solid particles e.g. sprays - Injectors are used to define the entrance of the droplets into the domain - Supplementary models: Drag force, turbulent dispersion, erosion, wall interaction, droplet atomization and breakup, evaporation, Coulomb forces - Discrete Element Model (DEM) - Used to study the behavior of discrete particles and how they interact (slide/bounce etc) with each other - Suplementary models: Drag force, particle cohesion, particle bonding and breaking, turbulent dispersion - Fluid film - To model transport and energy transfer of thin fluid films - Suplementary models: Wave & edge based stripping Heat Transfer and Conjugate Heat Transfer - Conduction, Convection - Radiation - Surface to surface, solar and discrete ordinates (DOM) Combustion and Chemical Reaction - Coal combustion, Eddy Break-up (EBU), Homogeneous reactor, Coherent Flame Model (CFM), Partially Pre-mixed Coherent Flame Model (PCFM), Presumed Probability Density Function (PPDF), Progress variable model (PVM), Thickened flame model, Soot moments emission Multiphysics - Solid Stress: small and large deformations formulation - Battery simulation: Simulation of coupled electric and thermal fields in batteries - Electromagnetic Field Simulation - Fluid Structure Interaction and Dynamic Fluid Body Interaction - Import/map/export CAE models Optional models - Passive scalar - to visualise tracers e.g. Smoke dispersal - Co-simulation - Coupling to 1D & 3D CAE tools - Thin Film - Models de-fogging and de-icing - Aeroacoustics: Identification of broadband noise sources and far field propagation - Melting and Solidification - Gravity STAR-CCM+ v7 Quick Reference Guide 04

5 ...Through to Post-processing Tip: Volume Mesh or Solution View Representation Must Be Acitve Creating New Scenes Right Click Scenes > New Scene Scenes are made up of different displayers with different properties applied to each Different scene types contain a default set of displayers, more may be added once the scene has been created Change opacity of a displayer to create overlay effect Scene in Scene feature, creating composite scenes Menu Bar Displayers Scalar displayer Scalar Color Bar Solution History Record replay, and review results from transient or steady state simulations. -- Solutions are stored in a.simh file To create a new solution history: -- Right click on Solution Histories > New -- Choose a file name -- If auto recording, make sure "Auto-record is ticked" and select update rule and frequency (time step, iteration etc) -- Choose scalar and vector functions to record -- Choose regions to use To load an existing solution history -- Right click on Solution Histories > Load To load instantaneous solution data into a solution history -- Right click on the solution history > create snapshot - To view recorded results -- Right click on solution history > create recorded solution view -- under "Solution views" choose by state name, index, iteration, time setup or solution time -- drag and drop solution view into scene or choose in a representation drop-down To animate results choose what data to cycle through and cylcle properties under animation Displayer types Geometry - Used to display geometry - Colour, opacity and shading may be altered Scalar - To plot field functions on parts - Can be displayed as filled (with or without mesh), smooth filed and as contours Vector - To plot vector quantities - Vector styles/distributions may be altered Streamline - Only used to display streamlines - Streamlines may be plotted as tubes, lines or ribbons - May be animated using the toolbar Particle Track - To display droplet paths for lagrangian phase Applying a Representation Expand Representations + Drag the appropriate representation into the active scene Derived Parts Right Click Derived Parts > + Plane Sections + Iso-surfaces + Streamlines + Thresholds + Particle tracks + Probes Exporting a Scene Right Click on the Scene Name + Hard Copy for Static Image + Export STAR-View+ for interactive 3D Scene in free viewer STAR-CCM+ v7 Quick Reference Guide 05

6 STAR-CCM+ v7 Hotkeys In the Scene window Using the Mouse in the Visualization Display Action Hotkey Action Probe. Reset R Top View T Side View S Front View F Fit the View H <LMB> <MMB> Rotates the view. Moving the mouse horizontally will rotate the view around the vertical axis Moving the mouse vertically will rotate the view around the horizontal axis Moving the mouse at some angle, combines the two rotations Zooms the view in or out. Moving the mouse up, makes the view larger Moving the mouse down, makes the view smaller LMB = left mouse button. MMB = middle mouse button. RMB = right mouse button. <RMB> CTRL+<LMB> Pans the model across the screen Rotates the view around the axis perpendicular to the screen. Moving the mouse down rotates clockwise Moving it up rotates the view counter-clockwise In Surface Repair Action Browse Problem Areas First Problem Area Previous Problem Area Next Problem Area Last Problem Area Repair Delete Face Auto repair surface errors Delete Face Create Face from Vertices Collapse Vertices Smooth Vertices Split Edge Swap Edge Zip Edges Flag Feature Edge Unflag Feature Edge Fill Holes Fill Polygonal Patch Undo Redo Hotkey Up Left Right Down D A D V C M S W Z F U H P CTRL+Z CTRL+Y Action Hotkey Selection Controls Select None SHIFT+N Select/Deselect/Subset Select Zone SHIFT+Z Select/Deselect/Subset Select Geometric Range SHIFT+R Select/Deselect/Subset Boundaries SHIFT+B Grow Selection + Shrink Selection - Multi-Grow Selection SHIFT+M Select Attached Edges SHIFT+E Select Attached Vertices SHIFT+V Toggle face selection Alt+1 Toggle edge selection Alt+2 Toggle vertex selection Alt+3 Clear face selection SHIFT+1 Clear edge selection SHIFT+2 Clear vertex selection SHIFT+3 Display Controls Show All CTRL+A Hide All CTRL+SHIFT+A Show Selected CTRL+S Hide Selected CTRL+SHIFT+S Grow Displayed CTRL+ + Shrink Displayed CTRL+ - Show Faces on Boundaries CTRL+ B Hide Faces on Boundaries CTRL+SHIFT B STAR-CCM+ v7 Quick Reference Guide 06

7 Using Tools Tools can help add additional complexity and features to a simulation Annotations Simple text. 2D, 3D, background, plot and scene images. Iteration/time step display. CD-adapco and company logos. Scene information. Scene Grid. Colormaps Create user defined color maps for use in post processing displayers. Coordinate Systems Laboratory system. Local coordinate system: Cartesian, cylindrical, spherical. Block-mapped coordinate system: to create section surfaces along periodic directions. Co-Simulation Couple STAR-CCM+ to CAE tools. Data Mappers Map simulation results to surfaces and volumes for CAE integration. Data Set Functions Perform a Fast Fourier Transform (FFT) on data. Used for frequency analysis in aeroacoustics. Field Functions A mechanism by which fields (raw data from the simulation stored in the cells, and/or on the boundaries) may be viewed and defined in STAR-CCM+. - System Field and User Field Functions. - Scalar Field and Vector field Function. Layouts Store the layout of the STAR-CCM+ interface. Databases Access to information on a material properties used when selecting physics models. Motions Create motions for modeling moving objects such as turbomachines & floating bodies. Reference frames Create frames of reference for post processing and rotating/translating objects. Tables To specify tabular data for the simulation, particularly for boundary conditions and/or initial conditions (e.g. fan curves). To extract and export tabular data from the simulation, including accumulated forces, i.e. to use as boundary conditions for other simulations. Transforms Used by displayers to modify the default position, orientation, or size of the part in the displayer. Transforms can repeat or mirror parts, or just reposition, resize, or reorient them. The transform feature is for viewing only. Units A flexible and customizable support for engineering units allows to view default units and create user defined units. User code Allows STAR-CCM+ to be customized with functions written in a compiled language such as C, C++ or Fortran. Views The position and angle of the view in a scene may be saved and copied. Stored views allow for repeatable post-processing. Volume Shapes Creates shapes for volumetric controls. STAR-CCM+ v7 Quick Reference Guide 07

8 The STAR-CCM+ Workspace Menu Bar Toolbar Explorer Plane Graphics Window Properties Window Output Window Toolbars Description Save Save All Cut Copy Paste Start Recording Pause Recording System Edit Macro New Simulation Import Mesh Play Macro StopRecording Load Simulation ImportSurface InitializeMesh Create Volume Mesh Initialize Solution Run Fit Plan Mesh Generation Solution Plots Clear Mesh CreateSurfaceMesh Step Stop Create/Open Plots Zoom Create Transform Sketch Plane Create Extrude Create Revolve Create Sweep Create Fillet SelectionFilter 3D-CAD Zone Select Create Sketch Create Extrude Cut Create Revolve Cut Create Loft Create Chamfer Rubberband Select Zone Select Fit Rotate View Redo View CreateSection Toggle mesh Step Backward Write Movie Visualization Animation Create/Open Scenes Box Zoom Undo View Transparent Measure Distance Play/Pause Stop Step Forward STAR-CCM+ v7 Quick Reference Guide 01